Currently, most of well-known electric generators generate electric current by prime mover driving the rotator to rotate so as to cause magnetic induction at a coil. However, magnetic field induced by coil tends to impede rotation of the rotator. The electric power obtained by this method is quite undesirable. Therefore, it is quite urgent for people to solve the problem of raising power converting efficiency of an electric generator. A patent application (Publication No. is CN1405955) provides a “High-Quality Low-Consumption Electric Generator” which does not solve the problem of low work-energy converting efficiency of an electric generator although it has solves a problem of voltage adjusting in a permanent magnetic electric generator. A patent application (Publication No. is CN1036484) provides “A Novel Brushless Electric Generator” which raises output electric current of an electric generator, but there still exists very strong magnetic repelling-attracting force when a stator and a rotator of an electric generator are working, it is still needed to apply a large amount of work for the prime mover to drive the rotator to rotate so as to overcome the magnetic repelling-attracting force of field, and it also does not solve the problem of low work-energy converting efficiency of an electric generator.